GREEN BAY, Wis. — Two years ago, Sam Barrington was a seventh-round pick just hoping to make the Green Bay Packers’ active roster. A rookie season without a single defensive snap found Barrington near the back of the inside linebacker depth chart entering 2014.

Barrington’s career path soon changed, though. The struggles of A.J. Hawk, Brad Jones and Jamari Lattimore opened a door for Barrington to become a full-time starter in Week 13. It was an opportunity he took advantage of and a spot he kept through the playoffs.

As Barrington enters the third year of his NFL career, he’s now standing alongside Clay Matthews as the starting inside linebackers on the Packers defense. That’s the type of quick rise up the ranks that would have many feeling good about their accomplishments.

As Green Bay’s organized team activities began, Barrington was with the starting defense on every snap. Over the final seven games last season, Barrington was on the field for more than 78 percent of the defensive snaps.

Even as he finds himself a key piece of the Packers’ plans in 2015, Barrington’s goals have him wanting a lot more.

"Of course everybody wants to make the Pro Bowl, everybody wants to be the No. 1 inside linebacker in the league, but I feel I have so much to do as far as improving myself," he said. "I’m just going to continue getting better every day and reap the benefits of my work."

Barrington is a fiery, intense player. It’s of little surprise that someone with his mindset would feel relatively inconsequential at this stage.

It’s that exact type of attitude that had defensive lineman Mike Daniels singing Barrington’s praises late last season. Daniels loved the energy that Barrington brought to the group. When Daniels heard a "thud" somewhere on the field, he knew he was likely to look up and find Barrington standing over a fallen ball-carrier.

"He takes this seriously," Daniels said. "Things don’t go right, it bothers him. He’s going to hold himself and his teammates accountable. To have a guy like that, he will get vocal on top of doing the right things. I really appreciate him. I do.

"I’m glad he’s had his opportunity because I knew he was going to do something once he had it."

Barrington wasn’t ready to publicly express how a successful upcoming season would be defined for his own play. But it sure seems like it would take a record-breaking individual season for Barrington to even consider grading himself out positively.

"I feel like if you sit here and you say you’re satisfied, I don’t know how much of a player you are," Barrington said. "This is a game of never-ending satisfaction. I think it’s all about continuing to come in, work every day. I’m not satisfied. I don’t think I’ve done that much."

Part of Barrington’s approach might be a reaction to the way his position coach, Winston Moss, addresses topics such as these with the linebacker group.

"We’re in the wait-and-see to where exactly he’s going to go again," Moss said of Barrington. "You can look a certain way in practice and so forth, and make him be good somehow of a measurement compared to your players, but not until you get to the games."

In game action last season, Barrington had 47 tackles, four missed tackles and three quarterback hits after he became a starter. However, he graded out in the negatives in the ProFootballFocus rating system (minus-8.9) in those games.

But there is a big difference between stepping into a significant role late in the season for a team that nearly made the Super Bowl and actually getting an offseason to work at that spot.

"It’s very beneficial," Barrington said. "We (Matthews and I) both did some good things throughout the end of the season last year, but we both were pretty new at what we were doing as far as game experience. It’s going to be pretty exciting to see what’s going to happen this season from the both of us."

Though Matthews is a five-time Pro Bowl selection, it’s Barrington who’s actually the more experienced of the two on the inside. Matthews said he’s finally learning the nuances of the inside linebacker position this offseason. Those are all things that Barrington learned many years ago.

Expectations will be much higher for Barrington now. He doesn’t want to be the new Hawk, Jones and Lattimore, whose inefficient play leads to someone behind him on the depth chart — such as Jake Ryan, Carl Bradford or Joe Thomas — taking his place.

But no matter how well Barrington might play, a fair assumption would be that it’s not good enough for him.

"Yeah, I was a seventh-round pick, I didn’t play much defense my first year, but all along, I had it in my mind what I’m supposed to accomplish," he said. "I won’t be satisfied until I hang my helmet up one day. I’m not satisfied at all right now."